Pros
They hire in very large numbers and are often more willing to take a chance on freshers with diverse educational backgrounds or lower GPAs compared to top product-based firms. These firms have long-term contracts with Fortune 500 companies, governments, and other large organizations. This provides a high degree of financial stability and job security that many startups and even some product companies cannot match. They have a clear, well-trodden career ladder (e.g., Analyst → Associate → Senior Associate → Team Lead → Manager). You know exactly what is required to get to the next level in terms of years of experience and skills. In summary, service-based companies are not for everyone, but they are far from a sign of "lost hope."
Cons
Cognizant hires many freshers, but the actual work can be restrictive, often limited to software testing and minor updates. Expect to work overtime to meet deadlines. A significant downside is the sometimes dismissive attitude from senior staff, which creates a challenging environment for those trying to learn and grow.